JP2019219491A - Image forming apparatus - Google Patents

Abstract

To provide an image forming apparatus that has a cleaner located between a photoconductor drum and a fuser in the vertical direction, the image forming apparatus capable of smoothly conveying a waste toner from the cleaner to a waste toner storage container.SOLUTION: An image forming apparatus 1 comprises: a photoconductor drum 13; a cleaner 33; a waste toner storage container 34; and a waste toner conveyance pipe 35. The cleaner 33 is located between the photoconductor drum 13 and a fuser 9 in the vertical direction and cleans a peripheral surface of the photoconductor drum 13 after a toner image is transferred to a print medium P. The waste toner storage container 34 is located below the cleaner 33 while separated from the cleaner 33 and stores a waste toner removed by the cleaner 33 from the peripheral surface of the photoconductor drum 13. The waste toner conveyance pipe 35 connects the cleaner 33 and the waste toner container 34 and conveys the waste toner from the cleaner 33 to the waste toner storage container 34.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to an image forming apparatus.

  Conventionally, an image forming apparatus includes a photosensitive drum, a cleaner, a waste toner container, and a waste toner conveying pipe. The cleaner cleans the peripheral surface of the photosensitive drum after the toner image has been transferred to the print medium. The waste toner container stores the waste toner removed from the peripheral surface of the photosensitive drum by the cleaner. The waste toner transport pipe transports the waste toner from the cleaner to the waste toner container (see Patent Document 1 below).

JP 2016-110097 A

  In the image forming apparatus as described in Patent Document 1, the waste toner transport pipe transports the waste toner substantially horizontally from the cleaner to the waste toner container.

  Therefore, the waste toner easily accumulates near the inner surface below the waste toner conveying pipe. Further, when the accumulated waste toner is pressed between the screw and the inner surface of the waste toner conveying pipe, the waste toner conveying pipe may be clogged.

  In view of the above, an object of the present disclosure is to provide an image forming apparatus in which a cleaner is located between a photosensitive drum and a fixing device in a vertical direction and can smoothly transport waste toner from a cleaner to a waste toner container. Is to do.

  (1) The image forming apparatus of the present disclosure forms an image on a print medium. The image forming apparatus includes a photosensitive drum, an exposing device, a developing device, a toner container, a transfer roller, a fixing device, a cleaner, a waste toner container, and a waste toner conveying pipe. The photosensitive drum is rotatable about a rotation shaft extending in the axial direction. The exposure device exposes the photosensitive drum to form a latent image. The developing device has a developing roller. The developing roller develops the latent image formed on the photosensitive drum with toner to form a toner image. The toner container stores the toner supplied to the developing roller. The transfer roller transfers the toner image formed on the photosensitive drum to a print medium. The fixing device fixes the toner image transferred to the print medium to the print medium. The fixing device is located above the photosensitive drum with a space therebetween. The cleaner cleans the peripheral surface of the photosensitive drum after the toner image has been transferred to the print medium. The waste toner container stores the waste toner removed from the peripheral surface of the photosensitive drum by the cleaner. The waste toner transport pipe transports the waste toner from the cleaner to the waste toner container. The cleaner is located between the photosensitive drum and the fixing device in the vertical direction. The developing device is located below the photosensitive drum. The waste toner container is located below the cleaner. The toner container covers at least a part of the upper surface of the waste toner container.

  According to such a configuration, the waste toner transport pipe transports the waste toner from the cleaner located between the photosensitive drum and the fixing device in the vertical direction to the waste toner container located below the cleaner.

  Thus, the waste toner removed from the peripheral surface of the photosensitive drum by the cleaner can be conveyed from the cleaner to the waste toner container using gravity.

  As a result, the waste toner can be smoothly transported from the cleaner to the waste toner container.

  (2) The image forming apparatus may further include a main body housing, a drawer, a drum cartridge, and a developing cartridge. The main body housing houses an exposure device, a transfer roller, and a fixing device. The main body housing has an opening and a cover. The cover is movable between an open position that opens the opening and a closed position that closes the opening. The drawer is movable via the opening between an inner position located inside the main body housing and an outer position located outside the main body housing. The drum cartridge has a photosensitive drum, a cleaner, a waste toner container, and a waste toner conveying pipe. The drum cartridge can be mounted on a drawer. The developing cartridge has a developing device and a toner container. The developing cartridge can be mounted on a drum cartridge.

  (3) The cover may support the drawer with the cover located at the open position and the drawer located at the outer position.

  (4) The drawer may move upward as it moves from the outer position to the inner position.

  (5) The developing cartridge may be attachable to the drum cartridge while the cover is located at the open position and the drawer is located at the outer position, while the drum cartridge is attached to the drawer.

  (6) When the developing cartridge is mounted on the drum cartridge, the waste toner container may guide the developing cartridge by bringing the upper surface of the waste toner container into contact with the lower surface of the developing cartridge.

  (7) The image forming apparatus may include a cassette, a pickup roller, a second paper feed tray, and a second pickup roller. The cassette is capable of storing a print medium. The cassette is mountable on the main body housing, and is located below the drawer located at the inner position when mounted on the main body housing. The pickup roller picks up the print medium in the cassette. The second paper feed tray can hold a print medium. The second pickup roller picks up the print medium placed on the second paper feed tray. The cover has a second opening through which the print medium placed on the second paper feed tray passes.

  (8) The pickup roller and the second pickup roller may be located closer to the fixing device than to the opening when the cover is located at the closed position.

  (9) The transfer roller may be provided on the drum cartridge.

  (10) The waste toner transport pipe may intersect with the toner container when viewed from the axial direction.

  According to the image forming apparatus of the present disclosure, in an image forming apparatus in which the cleaner is positioned between the photosensitive drum and the fixing device in the vertical direction, the waste toner can be smoothly transported from the cleaner to the waste toner container.

FIG. 1 is a schematic configuration diagram of the image forming apparatus according to the first embodiment. FIG. 2 shows a state in which the drawer shown in FIG. 1 is located at the outer position and the developing cartridge has been removed from the drawer. FIG. 3 is an explanatory diagram for explaining a scanning range of the laser scanning unit shown in FIG. FIG. 4 is a plan view of the drawer shown in FIG. FIG. 5 is a sectional view of the drawer shown in FIG. FIG. 6 is a plan view of the drum cartridge shown in FIG. FIG. 7 is a sectional view taken along line BB of the drum cartridge shown in FIG. FIG. 8 is a side view of the drum cartridge shown in FIG. FIG. 9 is a schematic configuration diagram of an image forming apparatus according to the second embodiment. FIG. 10 shows a state where the drawer shown in FIG. 9 is located at the outer position.

1. Overview of Image Forming Apparatus of First Embodiment An overview of an image forming apparatus 1 of a first embodiment will be described with reference to FIGS.

  As shown in FIG. 1, the image forming apparatus 1 forms an image on a print medium P. The image forming apparatus 1 includes a main body housing 2, a paper feed unit 3, a drawer 4, a drum cartridge 5, an exposure unit 6, a developing cartridge 7, a transfer roller 8, and a fixing unit 9.

1.1 Main Unit Housing The main unit housing 2 accommodates a paper feed unit 3, a drawer 4, a drum cartridge 5, an exposing unit 6, a developing cartridge 7, a transfer roller 8, and a fixing unit 9. The main body housing 2 has an opening 2A and a cover 2B.

  The opening 2 </ b> A is located on the opposite side of the transfer roller 8 with respect to the drum cartridge 5 when the drum cartridge 5 is mounted on the main body housing 2.

  The cover 2B is movable between an open position for opening the opening 2A (see FIG. 1) and a closed position for closing the opening 2A (see FIG. 2).

1.2 Paper Feed Unit The paper feed unit 3 is configured to supply the print medium P to the photosensitive drum 13. The print medium P is, for example, printing paper. The photosensitive drum 13 will be described later. The paper feed unit 3 includes a cassette 10, a pickup roller 11, a paper feed roller 12, and a transport roller 17. The cassette 10 can store the print medium P. The cassette 10 can be mounted on the main housing 2. The cassette 10 is located below the drawer 4 located at the inner position when mounted on the main body housing 2. The inside position of the drawer 4 will be described later. The pickup roller 11 is configured to pick up the print medium P in the cassette 10 and transport the print medium P toward the paper feed roller 12. The pickup roller 11 is located closer to the fixing device 9 than the opening 2A in the horizontal direction with the cover 2B located at the closed position. The paper feed roller 12 is configured to transport the print medium P from the pickup roller 11 toward the transport roller 17. The transport roller 17 is configured to transport the print medium P from the paper feed roller 12 toward the photosensitive drum 13.

1.3 Drawer The drawer 4 is movable between an inner position (see FIG. 1) and an outer position (see FIG. 2), as shown in FIGS. When the drawer 4 is located at the inside position, the drawer 4 is located inside the main body housing 2. When the drawer 4 is located at the outer position, the drawer 4 is located outside the main body housing 2. The drawer 4 is movable between an inside position and an outside position via the opening 2A with the cover 2B located at the open position. The drawer 4 moves upward as it moves from the outer position to the inner position. In other words, the drawer 4 moves downward as it moves from the inside position to the outside position. The drawer 4 supports the drum cartridge 5 and the developing cartridge 7. The drawer 4 is movable between an inside position and an outside position while supporting the drum cartridge 5 and the developing cartridge 7. The drawer 4 is stopped at the outer position by contacting a part of the main body housing 2.

  More specifically, as shown in FIG. 2, the main body housing 2 has a guide groove 2C. The guide groove 2C extends in the moving direction of the drawer 4. The guide groove 2C has a first end E1 and a second end E2 in the moving direction of the drawer 4. The second end E2 is located away from the first end E1 in the moving direction of the drawer 4. The drawer 4 has a projection 4A (see FIGS. 4 and 5). The projection 4A is located on the side surface of the drawer 4 in the axial direction in which the rotation axis A1 of the photosensitive drum 13 extends. The protrusion 4A fits into the guide groove 2C. This allows the drawer 4 to move along the guide groove 2C. That is, the guide groove 2 </ b> C guides the movement of the drawer 4. When the drawer 4 moves from the outer position to the inner position, the protrusion 4A is guided by the guide groove 2C and moves from the first end E1 to the second end E2. When the drawer 4 reaches the inside position, the protrusion 4A contacts the second end E2 of the guide groove 2C, and the drawer 4 stops at the inside position. At this time, the photosensitive drum 13 comes into contact with the transfer roller 8. When the drawer 4 moves from the inner position to the outer position, the protrusion 4A comes into contact with the inner surface of the first end E1 of the guide groove 2C, that is, a part of the main body housing 2, so that the drawer 4 moves to the outer position. Can be stopped.

  In addition, the drawer 4 is supported by the cover 2B located at the open position while being located at the outer position. That is, the cover 2B supports the drawer 4 in a state where the cover 2B is located at the open position and the drawer 4 is located at the outer position. Specifically, the cover 2B has a support 2D. The support portion 2D contacts the lower surface of the drawer 4 with the cover 2B positioned at the open position and the drawer 4 positioned at the outer position. Thereby, the support part 2D supports the drawer 4 located at the outer position. The support 2D has a plurality of guide rollers 2E. The plurality of guide rollers 2E contact the lower surface of the drawer 4 with the cover 2B located at the open position and the drawer 4 located at the outer position. Thereby, the drawer 4 can move smoothly while being supported by the cover 2B.

  Further, as shown in FIGS. 1 and 2, the drawer 4 includes an opposing roller 18. When the drawer 4 is located at the inner position, the opposing roller 18 comes into contact with the transport roller 17. With the opposing roller 18 in contact with the transport roller 17, the opposing roller 18 is rotatable with the rotation of the transport roller 17. Thus, with the drawer 4 located at the inner position, the opposing roller 18 can transport the print medium P from the paper feed roller 12 to the photosensitive drum 13 together with the transport roller 17. Further, when the drawer 4 moves from the inside position to the outside position, the opposing roller 18 is separated from the transport roller 17. Accordingly, when the print medium P is clogged between the transport roller 17 and the opposing roller 18, the user separates the opposing roller 18 from the transport roller 17 by positioning the drawer 4 at the outer position, and the jammed printing is performed. The medium P can be removed.

1.4 Drum Cartridge As shown in FIG. 1, the drum cartridge 5 can be mounted on the drawer 4. The drum cartridge 5 has a photosensitive drum 13 and a charging roller 14. That is, the image forming apparatus 1 includes the photosensitive drum 13.

  The photosensitive drum 13 is rotatable about a rotation axis A1 extending in the axial direction. The axial direction intersects the moving direction of the drawer 4. Preferably, the axial direction is orthogonal to the moving direction of the drawer 4. The photosensitive drum 13 extends in the axial direction and has a cylindrical shape. In the present embodiment, with the drum cartridge 5 and the developing cartridge 7 mounted on the drawer 4 and the drawer 4 positioned at the inner position, the photosensitive drum 13 moves vertically with respect to the paper feed roller 12 and the fixing device 9. Located between.

  The charging roller 14 charges the peripheral surface of the photosensitive drum 13. The charging roller 14 contacts the peripheral surface of the photosensitive drum 13. The drum cartridge 5 may include a non-contact charger such as a scorotron charger instead of the charging roller 14.

1.5 Exposure Unit The exposure unit 6 exposes the photosensitive drum 13 to form a latent image. Specifically, the exposure device 6 exposes the peripheral surface of the photosensitive drum 13 charged by the charging roller 14. As a result, a latent image is formed on the peripheral surface of the photosensitive drum 13. The exposure unit 6 is located above the drawer 4 located at the inside position. Specifically, the exposure device 6 is a laser scan unit that scans the peripheral surface of the photosensitive drum 13 with the laser light L. As shown in FIG. 3, the laser light L traveling from the exposure device 6 to the photosensitive drum 13 is applied to the drum cartridge 5 in the axial direction in a state where the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the inner position. It passes between the drum first side plate 31 and the drum second side plate 32.

1.6 Developing Cartridge As shown in FIG. 1, the developing cartridge 7 can be mounted on the drum cartridge 5. The developing cartridge 7 has a developing device 7A and a toner container 7B. That is, the image forming apparatus 1 includes the developing device 7A and the toner container 7B.

  The developing device 7A has a developing roller 16. That is, the developing device 7A is a part of the developing cartridge 7 that supports the developing roller 16. The developing device 7A is located below the photosensitive drum 13 in a state where the drum cartridge 5 and the developing cartridge 7 are mounted on the drawer 4.

  The developing roller 16 is located below the photosensitive drum 13 in a state where the drum cartridge 5 and the developing cartridge 7 are mounted on the drawer 4. The developing roller 16 contacts the photosensitive drum 13 with the drum cartridge 5 and the developing cartridge 7 mounted on the drawer 4. Thus, the developing roller 16 can supply the toner in the developing cartridge 7 to the photosensitive drum 13 in a state where the drum cartridge 5 and the developing cartridge 7 are mounted on the drawer 4. The developing roller 16 develops a latent image formed on the photosensitive drum 13 with the toner by supplying the toner in the developing cartridge 7 to the photosensitive drum 13 to form a toner image on the peripheral surface of the photosensitive drum 13. The developing roller 16 is rotatable about a rotation axis A2. The rotation axis A2 of the developing roller 16 is parallel to the rotation axis A1 of the photosensitive drum 13. The developing roller 16 has a shaft 16A and a roller body 16B.

  The shaft 16A extends in the axial direction along the rotation axis A2. The shaft 16A has a cylindrical shape. The shaft 16A passes through the roller body 16B in the axial direction. The shaft 16A is made of metal.

  The roller body 16B extends in the axial direction. The roller body 16B has a cylindrical shape. The roller main body 16B is made of conductive rubber.

  The toner container 7B stores the toner supplied to the developing roller 16. That is, the toner container 7B is a part of the developing cartridge 7 that stores toner. The internal space of the toner container 7B communicates with the internal space of the developing device 7A. Thus, the toner in the toner container 7B is supplied to the developing roller 16 of the developing device 7A.

1.7 Transfer Roller The transfer roller 8 comes into contact with the photosensitive drum 13 in a state where the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the inner position. The print medium P from the cassette 10 passes between the transfer roller 8 and the photosensitive drum 13. At this time, the transfer roller 8 transfers the toner image formed on the photosensitive drum 13 to the print medium P.

1.8 Fixing Unit The fixing unit 9 heats and pressurizes the printing medium P to which the toner image has been transferred, and fixes the toner image transferred to the printing medium P to the printing medium P. The fixing device 9 is located above the photosensitive drum 13 with a space therebetween in a state where the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the inner position. That is, the image forming apparatus 1 is installed on a horizontal table or the like such that the fixing device 9 is positioned above the photosensitive drum 13 in the vertical direction.

2. Next, details of the drawer 4 will be described with reference to FIGS. 4 and 5.

  As shown in FIG. 4, the drawer 4 includes a first drawer side plate 21, a second drawer second side plate 22, and a bottom plate 23.

  The drawer first side plate 21 is located at the first end of the drawer 4 in the axial direction. The drawer first side plate 21 extends in the moving direction of the drawer 4. As shown in FIG. 5, the drawer first side plate 21 has a first end E11 and a second end E12 in the moving direction of the drawer 4. The second end E12 is located away from the first end E11 in the moving direction of the drawer 4. The second end E12 is located downstream of the first end E11 in the direction in which the drawer 4 moves from the inside position to the outside position. The drawer first side plate 21 has a guide 24, a through hole 26, and a notch 27.

  The guide 24 is located on the inner surface of the first drawer side plate 21 in the axial direction. The guide 24 is recessed in a direction away from the second drawer side plate 22 in the axial direction. The guide 24 is located between the first end E11 and the second end E12 in the moving direction of the drawer 4. The guide 24 extends in a direction intersecting the moving direction of the drawer 4. The guide 24 has a first end E21 and a second end E22. The first end E21 is located closer to the first end E11 than the second end E22 in the moving direction of the drawer 4. The first end E21 is connected to the notch 27. The second end E22 is located closer to the second end E12 than the first end E21 in the moving direction of the drawer 4. The guide 24 is inclined downward from the second end E22 toward the first end E21. When the drawer 4 is located at the outer position, the second end E22 (see FIG. 2) of the guide 24 is exposed to the outside from the opening 2A of the main body housing 2. When the drum cartridge 5 is attached to the drawer 4 in a state where the drawer 4 is located at the outer position, the projection 5A of the drum cartridge 5 fits into the guide 24 (see FIG. 6). Thus, the guide 24 guides the protrusion 5A of the drum cartridge 5 when the drum cartridge 5 is mounted on the drawer 4 in a state where the drawer 4 is located at the outer position.

  The through hole 26 is located below the guide 24 in the vertical direction. The through hole 26 has a circular shape. With the developing cartridge 7 mounted on the drum cartridge 5 and the drum cartridge 5 mounted on the drawer 4, the developing coupling (not shown) of the developing cartridge 7 is exposed through the through hole 26. In a state where the developing cartridge 7 is mounted on the drum cartridge 5 and the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the inner position, a first main body coupling (not shown) is provided in the developing coupling. Be linked. At this time, the first main body coupling is inserted into the through hole 26.

  The notch 27 connects to the first end E21 of the guide 24. The notch 27 has a semicircular shape. With the drum cartridge 5 mounted on the drawer 4, the projection 5A of the drum cartridge 5 fits into the notch 27, and the drum coupling 100 (see FIG. 6) is exposed through the notch 27. A second main body coupling (not shown) is connected to the drum coupling 100 in a state where the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the inner position. At this time, the second main body coupling is inserted into the notch 27.

  The drawer second side plate 22 is located at the second end of the drawer 4 in the axial direction as shown in FIG. The drawer second side plate 22 is located apart from the drawer first side plate 21 in the axial direction. The drawer second side plate 22 has the same shape as the drawer first side plate 21 except that it does not have the through hole 26.

  The bottom plate 23 is located between the first drawer side plate 21 and the second drawer side plate 22 in the axial direction. The bottom plate 23 extends in the axial direction. The first end of the bottom plate 23 in the axial direction is connected to the first drawer side plate 21. The second end of the bottom plate 23 in the axial direction is connected to the second drawer side plate 22. The bottom plate 23 has an opening 23A.

  The opening 23A extends in the axial direction. In a state where the drawer 4 is located at the inner position and the cover 2B is located at the closed position, two pressing members 110A and 110B provided in the main body housing 2 are located within the opening 23A.

  1 and 2, the pressing member 110A can move between a pressing position (see FIG. 1) and a pressing release position (see FIG. 2) via the opening 23A.

  The pressing member 110A is connected to the cover 2B via a bar 111 and a tension spring 112. The pressing member 110A moves from the pressing release position to the pressing position in conjunction with the movement of the cover 2B from the open position to the closed position. As shown in FIG. 1, the developing cartridge 7 is mounted on the drum cartridge 5, the drum cartridge 5 is mounted on the drawer 4, the drawer 4 is located at the inner position, and the cover 2B is located at the closed position. 110A is located at the pressing position. Then, the pressing member 110A presses the developing device 7A of the developing cartridge 7 toward the photosensitive drum 13. As a result, the developing roller 16 is pressed against the photosensitive drum 13.

  The pressing member 110A moves from the pressing position to the pressing release position in conjunction with the movement of the cover 2B from the closed position to the open position. As shown in FIG. 2, in a state where the cover 2B is located at the open position, the pressing member 110A is located at the pressure releasing position. Then, the pressing on the developing device 7A by the pressing member 110A is released.

3. Details of Drum Cartridge Next, details of the drum cartridge 5 will be described with reference to FIGS.

  As shown in FIG. 6, in addition to the photosensitive drum 13 and the charging roller 14, the drum cartridge 5 includes a drum first side plate 31, a drum second side plate 32, a cleaner 33, a waste toner container 34, And a waste toner transport pipe 35. That is, the image forming apparatus 1 includes a cleaner 33, a waste toner container 34, and a waste toner transport pipe 35.

3.1 First Drum Side Plate and Second Drum Side Plate The first drum side plate 31 is located at the first end of the drum cartridge 5 in the axial direction. The drum first side plate 31 extends in a direction intersecting the axial direction. Preferably, the first drum side plate 31 extends in a direction orthogonal to the axial direction. The first drum side plate 31 has a protrusion 5A, a guide 36, and a through hole 37 (see FIG. 7).

The projection 5A is located on the outer surface of the first drum side plate 31 in the axial direction. In other words,
The projection 5A is located on the opposite side of the drum second side plate 32 with respect to the drum first side plate 31 in the axial direction. The protrusion 5A extends in the axial direction. The protrusion 5A has a cylindrical shape. The protrusion 5A covers the peripheral surface of the drum coupling 100. That is, the guide 24 guides the drum coupling 100 to the notch 27 when the drum cartridge 5 is mounted on the drawer 4 with the drawer 4 located at the outer position. The drum coupling 100 is attached to the first end of the photosensitive drum 13 in the axial direction, and is rotatable together with the photosensitive drum 13. The drum coupling 100 receives power from the image forming apparatus 1 in a state where the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the inner position.

  As shown in FIG. 7, the guide 36 is located below the rotation axis A1 of the photosensitive drum 13 in a state where the drum cartridge 5 is mounted on the drawer 4. The shaft 16 </ b> A (see FIG. 1) of the developing roller 16 fits into the guide 36 when the developing cartridge 7 is mounted on the drum cartridge 5. Thus, the guide 36 guides the shaft 16A of the developing roller 16 when the developing cartridge 7 is mounted on the drum cartridge 5. The guide 36 has a first portion 36A and a second portion 36B.

  The first portion 36A extends in a direction intersecting the moving direction of the drawer 4 with the drum cartridge 5 mounted on the drawer 4. The first portion 36 </ b> A extends downward toward the photosensitive drum 13.

  The second portion 36B is located between the first portion 36A and the photosensitive drum 13. The second portion 36B extends in a direction crossing the direction in which the first portion 36A extends. Specifically, when the developing cartridge 7 is mounted on the drum cartridge 5 and the drum cartridge 5 is mounted on the drawer 4, the second portion 36B includes the rotation axis A1 of the photosensitive drum 13 and the rotation axis A2 of the developing roller 16. (See FIG. 1). The second portion 36B connects to the first portion 36A.

  The through hole 37 is located in the middle of the guide 36. The through hole 37 has a circular shape. In a state where the developing cartridge 7 is mounted on the drum cartridge 5, the through holes 37 are aligned with the through holes 26 (see FIG. 5) of the drawer 4 in the axial direction. Thus, in a state where the developing cartridge 7 is mounted on the drum cartridge 5 and the drum cartridge 5 is mounted on the drawer 4, the first main body coupling is connected to the developing coupling via the through hole 26 and the through hole 37. Be linked.

  The drum second side plate 32 is located at the second end of the drum cartridge 5 in the axial direction as shown in FIG. The drum second side plate 32 is located apart from the drum first side plate 31 in the axial direction. The drum second side plate 32 has a protrusion 5B. The drum second side plate 32 has the same shape as the drum first side plate 31 except that the drum second side plate 32 does not have the through hole 37 and has the protrusion 5B.

  The protrusion 5B is located on the outer surface of the drum second side plate 32 in the axial direction. In other words, the protrusion 5B is located on the side opposite to the drum first side plate 31 with respect to the drum second side plate 32 in the axial direction. The protrusion 5B extends in the axial direction. The protrusion 5B has a columnar shape. When the drum cartridge 5 is mounted on the drawer 4, the protrusion 5 </ b> B is fitted into a guide 24 (see FIG. 4) of the drawer second side plate 22, and is guided to the notch 27 by the guide 24. Accordingly, the guide 24 of the second drawer side plate 22 guides the projection 5B of the drum cartridge 5 when the drum cartridge 5 is mounted on the drawer 4 in a state where the drawer 4 is located at the outer position.

3.2 Cleaner The cleaner 33 is located around the photosensitive drum 13 as shown in FIG. The cleaner 33 is located vertically between the photosensitive drum 13 and the fixing device 9 (see FIG. 1) in a state where the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the inner position. The cleaner 33 cleans the peripheral surface of the photosensitive drum 13 after the transfer of the toner image onto the print medium P. Specifically, the cleaner 33 includes a cleaner frame 33A, a cleaning blade 33B, and a screw 33C.

  As shown in FIG. 6, the cleaner frame 33A is located between the first drum side plate 31 and the second drum side plate 32 in the axial direction. The cleaner frame 33A extends in the axial direction. A first end of the cleaner frame 33 </ b> A in the axial direction is connected to the first drum side plate 31. A second end of the cleaner frame 33A in the axial direction is connected to the drum second side plate 32. The cleaner frame 33A has an opening 33D as shown in FIG. The opening 33D faces the peripheral surface of the photosensitive drum 13. The opening 33D communicates with the internal space of the cleaner frame 33A. The opening 33D extends in the axial direction.

  The cleaning blade 33B is attached to the cleaner frame 33A. The end of the cleaning blade 33B is located inside the opening 33D. The end of the cleaning blade 33B contacts the peripheral surface of the photosensitive drum 13. Accordingly, when the photosensitive drum 13 rotates, the waste toner remaining on the peripheral surface of the photosensitive drum 13 is scraped off by the cleaning blade 33B, and is stored in the internal space of the cleaner frame 33A via the opening 33D. You. Thus, the cleaner 33 cleans the peripheral surface of the photosensitive drum 13.

  The screw 33C is located inside the cleaner frame 33A. The screw 33C extends in the axial direction. As a result, the screw 33C conveys the waste toner stored in the cleaner frame 33A in the axial direction.

3.3 Waste Toner Container The waste toner container 34 is located away from the cleaner 33 as shown in FIG. More specifically, when the drum cartridge 5 is mounted on the drawer 4, the drum cartridge 5 is located away from the cleaner 33 in the moving direction of the drawer 4. The waste toner container 34 is located below the cleaner 33 with the drum cartridge 5 mounted on the drawer 4. The waste toner container 34 stores the waste toner removed from the peripheral surface of the photosensitive drum 13 by the cleaner 33. Specifically, the waste toner removed from the peripheral surface of the photosensitive drum 13 by the cleaner 33 is transported from the cleaner 33 to the waste toner container 34 by the waste toner transport pipe 35 (see FIG. 8). The waste toner container 34 stores the waste toner transported by the waste toner transport pipe 35. The waste toner container 34 extends in the axial direction and has a box shape. The upper surface S1 of the waste toner container 34 extends in the same direction as the first portion 36A of the guide 36. The upper surface S1 of the waste toner container 34 extends downward as it approaches the photosensitive drum 13. As shown in FIG. 1, the upper surface S1 of the waste toner container 34 comes into contact with the lower surface S2 of the toner container 7B of the developing cartridge 7 in a state where the developing cartridge 7 is mounted on the drum cartridge 5. That is, with the developing cartridge 7 mounted on the drum cartridge 5, the toner container 7B covers at least a part of the upper surface of the waste toner container 34.

3.4 Waste Toner Transport Pipe As shown in FIG. 6, the waste toner transport pipe 35 connects the cleaner 33 and the waste toner container 34. The waste toner transport pipe 35 transports the waste toner from the cleaner 33 to the waste toner container 34. Specifically, a screw 35 </ b> A for transporting the waste toner is located in the waste toner transport pipe 35. The screw 35A is a shaftless screw. The waste toner transport pipe 35 passes outside the drum second side plate 32 in the axial direction. In other words, the waste toner transport pipe 35 passes on the side opposite to the drum first side plate 31 with respect to the drum second side plate 32 in the axial direction. Further, the waste toner conveying pipe 35 passes outside the scanning range (see FIG. 3) of the laser beam L from the exposure unit 6 in the axial direction. As shown in FIG. 8, when the drum cartridge 5 is mounted on the drawer 4, the waste toner transport pipe 35 moves from the cleaner 33 (see FIG. 7) to the waste toner container 34 when viewed from the axial direction. As it extends downward. Thus, the waste toner can be conveyed from the cleaner 33 toward the waste toner container 34 by using gravity. Therefore, the waste toner can be smoothly transported from the cleaner 33 to the waste toner container 34. As shown in FIG. 1, the waste toner conveying pipe 35 intersects with the toner container 7B when the developing cartridge 7 is mounted on the drum cartridge 5 when viewed from the axial direction.

4. Attachment of Drum Cartridge and Developing Cartridge to Drawer Next, attachment of the drum cartridge 5 and the developing cartridge 7 to the drawer 4 will be described.

  When the drum cartridge 5 is mounted on the drawer 4, the protrusion 5A (see FIG. 6) fits into the guide 24 (see FIG. 4) of the first drawer side plate 21 while the drawer 4 is located at the outer position, and the protrusion 5B The drum cartridge 5 is guided from the outside of the main body housing 2 toward the inside of the main body housing 2 by fitting the (see FIG. 6) the guide 24 (see FIG. 4) of the drawer second side plate 22.

  When the protrusion 5A fits into the notch 27 of the drawer first side plate 21 and the protrusion 5B fits in the notch 27 of the drawer second side plate 22, as shown in FIG. Is completed.

  With the drum cartridge 5 mounted on the drawer 4, at least a part of the drum cartridge 5 is located inside the main body housing 2. More specifically, the photosensitive drum 13 and the second portion 36 </ b> B of the guide 36 are located in the main body housing 2 in a state where the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the outer position. The first portion 36 </ b> A of the guide 36 of the drum cartridge 5 is located outside the main body housing 2 in a state where the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the outer position.

  Next, the developing cartridge 7 can be mounted on the drum cartridge 5 with the drum cartridge 5 mounted on the drawer 4 in a state where the cover 2B is located at the open position and the drawer 4 is located at the outer position. When the developing cartridge 7 is mounted on the drum cartridge 5, the shaft 16 </ b> A of the developing roller 16 is guided by the guide 36 of the drum cartridge 5 in a state where the drum cartridge 5 is mounted on the drawer 4 and the drawer 4 is located at the outer position. Is done. At this time, the waste toner container 34 guides the developing cartridge 7 when the upper surface S1 of the waste toner container 34 contacts the lower surface S2 of the developing cartridge 7. Then, as shown in FIG. 1, when the shaft 16A of the developing roller 16 is fitted into the second portion 36B of the guide 36 and the developing roller 16 contacts the photosensitive drum 13, the mounting of the developing cartridge 7 to the drum cartridge 5 is completed. .

5. According to the image forming apparatus 1, as shown in FIG. 1, the waste toner conveying pipe 35 is disposed below the cleaner 33 from the cleaner 33 located between the photosensitive drum 13 and the fixing device 9 in the vertical direction. The waste toner is conveyed to the located waste toner container 34.

  Thus, the waste toner removed from the peripheral surface of the photosensitive drum 13 by the cleaner 33 can be conveyed from the cleaner 33 to the waste toner container 34 using gravity.

  As a result, the waste toner can be smoothly transported from the cleaner 33 to the waste toner container 34.

  Further, according to the image forming apparatus 1, as shown in FIG. 2, the cover 2B supports the drawer 4 in a state where the cover 2B is located at the open position and the drawer 4 is located at the outer position.

  Thus, the drawer 4 can be stably supported at the outer position, and the drum cartridge 5 and the developing cartridge 7 can be replaced smoothly.

  According to the image forming apparatus 1, as shown in FIG. 2, the developing cartridge 7 is attached to the drawer 4 with the cover 2B at the open position and the drawer 4 at the outer position. It can be mounted on the drum cartridge 5 as it is.

  Thereby, only the developing cartridge 7 can be replaced without performing the operation of removing the drum cartridge 5 from the drawer 4.

  Therefore, the developing cartridge 7 can be replaced with a simple operation. At this time, since the toner container 7B of the developing cartridge 7 is located above the waste toner container 34, the waste toner container 34 does not interfere when the developing cartridge 7 is attached or detached.

  Further, according to the image forming apparatus 1, as shown in FIG. 2, when the developing cartridge 7 is mounted on the drum cartridge 5, the upper surface S1 of the waste toner container 34 is The developer cartridge 7 may be guided by contacting the lower surface S2 of the toner container 7B.

  Thus, the developing cartridge 7 can be mounted on the drum cartridge 5 while supporting the developing cartridge 7 on the upper surface S1 of the waste toner container 34.

  Therefore, the developing cartridge 7 can be replaced smoothly. In particular, even if the developing cartridge 7 is large and heavy, the developing cartridge 7 can be replaced smoothly.

6. Second Embodiment Next, a second embodiment will be described with reference to FIGS. In the second embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

6.1 Second Paper Feed Tray As shown in FIG. 9, the image forming apparatus 1 according to the second embodiment has a second opening 200, a second paper feed tray 201, a second pickup roller 202, and a second paper feed tray. And two paper feed rollers 203.

  The second opening 200 is provided in the cover 2B.

  The second paper feed tray 201 is a so-called multi-manual paper feed tray. The user can place a plurality of print media P2 on the second paper feed tray 201 through the second opening 200. The print medium P2 is usually a different type of print medium from the print medium P (see FIG. 1). For example, when the print medium P is A4 size print paper, the print medium P2 is a postcard or the like. The plurality of print media P2 placed on the second paper feed tray 201 is pulled into the main body housing 2 one by one through the second opening 200 by the second pickup roller 202. The second paper feed tray 201 has a first portion 201A and a second portion 201B.

  The first portion 201A is attached to an outer surface of the cover 2B. The first portion 201A is movable with respect to the cover 2B between a first position shown by a solid line in FIG. 9 and a second position shown by a virtual line in FIG. 9 in a state where the cover 2B is located at the closed position. It is. The second paper feed tray 201 is rotatable about a shaft A11 between a first position and a second position. When the cover 2B is located at the closed position and the first portion 201A is located at the first position, the first portion 201A is located on the opposite side of the second opening 200 of the cover 2B from the second portion 201B. When the cover 2B is located at the closed position and the first portion 201A is located at the first position, the first portion 201A extends substantially horizontally. When the cover 2B is located at the closed position and the first portion 201A is located at the second position, the first portion 201A extends vertically along the outer surface of the cover 2B.

  The second portion 201B is located inside the main body housing 2. More specifically, the second portion 201B is located between the drawer 4 and the cassette 10 in the up-down direction with the drawer 4 located at the inner position. The second portion 201B is positioned between the second pickup roller 202 and the first portion 201A in the horizontal direction with the cover 2B positioned at the closed position and the first portion 201A positioned at the first position. The second portion 201B extends substantially horizontally. The second portion 201B is connected to the first portion 201A with the cover 2B located at the closed position. Note that the connection between the first portion 201A and the second portion 201B is released when the cover 2B is located at the open position.

  The second pickup roller 202 is configured to convey the print medium P placed on the second paper feed tray 201 toward the second paper feed roller 203. The second pickup roller 202 is located closer to the fixing device 9 than the opening 2A in the horizontal direction with the cover 2B located at the closed position. Thereby, the thickness of the main body housing 2 can be reduced on the side where the cover 2B is provided. The second pickup roller 202 is located between the drawer 4 and the cassette 10 in the up-down direction with the drawer 4 located at the inner position.

  The second paper feed roller 203 is configured to transport the print medium P from the second pickup roller 202 toward the transport roller 17. The second paper feed roller 203 is located on the opposite side of the second opening 200 with respect to the second pickup roller 202 with the cover 2B located at the closed position. The second paper feed roller 203 is located between the drawer 4 and the cassette 10 in the vertical direction with the drawer 4 located at the inner position.

6.2 Transfer Roller In the image forming apparatus 1 according to the second embodiment, the transfer roller 8 is provided on the drum cartridge 5. Thus, the photosensitive drum 13 can be covered and protected by the transfer roller 8 in a state where the drum cartridge 5 is detached from the image forming apparatus 1.

6.3 Functions and Effects of Second Embodiment Also in the second embodiment, the same functions and effects as those of the above-described first embodiment can be obtained.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Main body housing 2A opening 2B cover 4 Drawer 5 Drum cartridge 6 Exposure device 7 Developing cartridge 7A Developing device 7B Toner container 8 Transfer roller 9 Fixing device 10 Cassette 11 Pickup roller 13 Photosensitive drum 16 Developing roller 33 Cleaner 34 Waste toner container 35 Waste toner transport pipe 200 Second opening 201 Second paper feed tray 202 Second pickup roller A1 Rotation axis P Print medium P2 Print medium

Claims (10)

An image forming apparatus that forms an image on a print medium,
A photosensitive drum rotatable about a rotation axis extending in the axial direction;
An exposure device that exposes the photosensitive drum to form a latent image;
A developing device having a developing roller for developing the latent image formed on the photosensitive drum with toner to form a toner image;
A toner container that stores toner supplied to the developing roller;
A transfer roller for transferring the toner image formed on the photosensitive drum to a print medium,
A fixing device for fixing the toner image transferred to the printing medium to the printing medium, wherein the fixing device is located above the photosensitive drum at an interval,
A cleaner for cleaning the peripheral surface of the photosensitive drum after the toner image is transferred to the print medium,
A waste toner container that stores waste toner removed from the peripheral surface of the photosensitive drum by the cleaner;
A waste toner transport pipe for transporting waste toner from the cleaner to the waste toner container;
With
The cleaner is located between the photosensitive drum and the fixing device in a vertical direction,
The developing device is located below the photosensitive drum,
The waste toner container is located below the cleaner,
The image forming apparatus, wherein the toner container covers at least a part of an upper surface of the waste toner container. The image forming apparatus further includes:
A main body housing that houses the exposure device, the transfer roller, and the fixing device, comprising: an opening; and a cover that is movable between an open position that opens the opening and a closed position that closes the opening. A body case,
Through the opening, a drawer movable between an inner position located in the main body housing and an outer position positioned outside the main body housing,
A drum cartridge having the photosensitive drum, the cleaner, the waste toner container, and the waste toner conveying pipe, wherein the drum cartridge is attachable to the drawer;
A developing cartridge having the developing device and the toner container, the developing cartridge being attachable to the drum cartridge;
The image forming apparatus according to claim 1, further comprising:   The image forming apparatus according to claim 2, wherein the cover supports the drawer in a state where the cover is located at the open position and the drawer is located at the outer position.   The image forming apparatus according to claim 2, wherein the drawer moves upward as it moves from the outer position to the inner position.   The developing cartridge may be mounted on the drum cartridge while the cover is located at the open position and the drawer is located at the outer position, while the drum cartridge is mounted on the drawer. The image forming apparatus according to claim 2, wherein:   The waste toner container guides the developing cartridge by contacting an upper surface of the waste toner container with a lower surface of the developing cartridge when the developing cartridge is mounted on the drum cartridge. The image forming apparatus according to claim 2, wherein: The image forming apparatus includes:
A cassette capable of storing a print medium, the cassette being mountable to the main body housing, and being positioned below the drawer positioned at the inner position while being mounted on the main body housing,
A pickup roller for picking up a print medium in the cassette;
A second paper tray on which print media can be placed;
A second pickup roller for picking up a print medium placed on the second paper feed tray,
The image forming apparatus according to claim 2, wherein the cover has a second opening through which a print medium placed on the second paper feed tray passes.   The image forming apparatus according to claim 7, wherein the pickup roller and the second pickup roller are located closer to the fixing device than the opening when the cover is located at a closed position.   The image forming apparatus according to claim 2, wherein the transfer roller is provided on the drum cartridge.   The image forming apparatus according to claim 1, wherein the waste toner transport pipe crosses the toner container when viewed from the axial direction.

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